Is it bad to shift an automatic tranny to neutral at the stop light?

My truck requires a lot of brake pressure to keep it from creeping forward at stop lights, so I usually shift it into neutral to relieve the pressure. Is this harmful to an automatic transmission if done over and over throughout the life of the vehicle?? Or for that matter, is it beneficial to the tranny to do this? Or neither here nor there?

 

i would also like to know this...my bf does it whenever he drives my truck

 

i heard its bad .. but then again.. thats what i have heard

 

no experience on this, i feel it's probably not great, as an automatic tranny shifts how it does for a reason. but I could be completely wrong

 

I would highly recommend leaving it in DRIVE and leaving your foot on the brake. This doesn't hurt anything.

Why? Because...if some idiot hits you in the rear while you're sitting there, you won't coast forward and hit the person in front of you.

 

I would see why it's idling so fast that it's hard to hold at a light while in gear.


No, it shouldn't hurt the tranny, it's designed to slip a little for exactly that reason.

--->Rob

 

I do this all the time. There are times when my engine lunges forward without warning and as long as my foot is on the brake they can hit me. I'll just call the Texas Hammer. I think it's the A/C kicking in but it really jumps so I pop it in neutral.

 

Actually, this is somewhat of a common misconception. If you know someone will hit you, it's actually MUCH better for all cars involved that you let your foot off the brake, allow the car to hit yours, and then once your car/truck is in motion from that collision, then use your brake to slow the vehicle down. This way, the energy transferred isn't dissipated in your rear bumper and or frame, and is instead dissipated as heat in your brakes. Inevitably there will always be energy lost through your exterior, and your truck won't be left scratchless, but overall better.

 

what if there is another car 10' in front of you?

 

According to Aamco, if you are stopped for a while, shifting into neutral is actually beneficial in reducing heat buildup in the tranny.

 

Hope to God that they too use the same method.

While I understand the ramifications in terms of insurance, there are some points to remember:

1. You shouldn't be so close that you won't be able to pull the manuever I detailed. You should be leaving enough room between you and the car in front of you. If you slam into the back of that car, I'm sure your insurance company will be asking that question or inquiring about the distance between the vehicles before impact.
2. When you make the choice to either brake and brace for impact, or allow them to hit you first and then apply the brakes, you're either saying, "I will guarantee all damage will be in my vehicle and it will be the worst of both scenarios", or "I am taking a chance that I can still keep the damage in my vehicle, and also lessen the damage done, or I might hit the vehicle in front of me". If you leave yourself enough room #2 should be an option
3. While I know you're thinking, "Yeah, but the dumbass behind me hit me! Insurance will pay for it!" Quite possibly, but just know that the force transferred into your vehicle will be guaranteed to be as big as or larger the other method, and you also risk transferring that force into your body, possible whiplash, etc..

Hopefully it's a situation no one finds themselves in, but regardless, biggest point is make sure you have enough distance between vehicles while at a stop.

If you start coming up with scenarios where the dude behind you hits you really hard, that's a mixed bag because you're pretty screwed regardless of when you decide to brake.

 

Makes sense.

Also leaving it in drive allows you to to get out of the way if you see someone is going to hit you in your mirror, assuming you aren't boxed in on the sides.

 

what size egg should i use? I'm 6'3 but not fat... XL or large should be fine?

 

Sure, an even better option. Why wait if you can safely get the hell out of the way.

Is that due to the friction that both have, or the amount of mass that each object respectively has (legitimate question)?

Instead, take two bricks OR two empty jugs, and put one on a sandpaper surface, and the other on ice, and I think that may be a better analogy.

I'd be interested to see someone carry this experiment out, haha

 

FWIW I have been doing the neutral at stoplights forever. I just feel in my own mind that taking the load off the drivetrain when not moving feels better to me.

 

This is all good in theory but in the real world even the best driver could never pull this off when rearended by thousands of pounds

 

Consider this, if you are hit from the rear, you will not be able to hold the brake down at some point, ESPECIALLY if you werent braced for impact.They studied that in the 80s,even had test crash video. After all the variables, a rear end accident makes them a lot of points moot , if they hit at 15+ your foot isnt likely to hold completely if at all.

As far as being in N for a light , it will wear out the components involved sooner. We do a LOT of stop and go, P to D shifting, in our work vehicles, by 50-75k miles they are a bit sloppy and often show in D when they are in N. I doubt if you do it sparingly there will be a problem.

 

All the manual transmission vehicles need it in Neutral when stopped for a while. If you want to leave it in Drive for safety reasons, then you might as well start scanning for carjackers and RPGs on rooftops. LOL treat every intersection as a potential kill zone.